Resistance welding is one type of welding process in which current is passed through the parts to be welded, and in many cases, the quality of the weld can vary. For instance, in regard to resistance spot welding processes, a welding gun has electrodes that close over multiple parts and apply pressure thereto. Then, high current is passed through the electrodes to create heat, which thereby creates a weld nugget that joins the parts together. The quality of the nugget depends on the amount of heat created, the amount of time the current is applied, the amount of pressure applied to the parts by the electrodes, and the amount of time pressure is applied by the electrodes.
Many welding guns are automated in order to control these parameters. For instance, some welding guns of the prior art utilize hydraulic and/or pneumatic devices to manipulate the electrodes for applying pressure to the part. Some of these welding guns include air switches, flow controls and time delays to control movement and pressure loading of the electrodes. Some of these welding guns also include load cells, position transducers, and/or processors to detect the load transferred from the electrodes to the parts. However, these means of moving, loading, and detecting the load of the electrodes can be costly, inaccurate, and complicated to operate and maintain.
Accordingly, there remains a need for a welding gun having a more cost effective, accurate, easy to operate and maintain means of moving, loading, and detecting the load of the electrode.